3 Things to Know About Mixing DDR4 and DDR5 RAM

You cannot mix DDR4 and DDR5 in the same system Motherboards are built for one memory standard only. Even if slots look similar, the notches, voltages, and controllers are different.

Forcing mismatched RAM into the wrong slots will prevent the system from posting The computer simply won’t start. Performance is irrelevant because the hardware is physically incompatible.

Ignore any motherboard claiming to support both standards That board does not exist for consumer hardware. If you see that claim, it is a typo or you misread the specs. Always buy matched sticks for your specific motherboard.